Preparing the Workpiece
The base metal should be cleaned up from all foreign materials (i.e. oil, grease, rust).
The cracks should be cleaned by opening (with an angle of approximately 90°) the welding bend and a stopper hole should be bored on both ends.
For welded connections the workpiece should be prepared by opening V, X or U welding bend (with an angle of approximately 90°) according to the material thickness.
The welding bend may be opened or carved by grinding method, with pneumatic tools or with OERLIKON E 900 mitering electrode. The surfaces on both sides of the welding bend (nearly 20 – 30 mm to the bend) should be cleaned by grinding.
Sharp edges and corners should be avoided.
Pre-Heating and Welding
If the welding is performed with electrode or oxyacetylene stick having the same chemical composition the whole workpiece should be homogenously pre-heated up to app. 600°C.
The welded piece should be cooled down slowly in furnace, hot sand or ash.